Special carton printing press



March'3, 1964 K. L. CRABTREE ETAL 3,

SPECIAL CARTON PRINTING PRESS 12 Sheets-Sheet 1 Filed Sept. 6. 1961 I N VEN TORS KEN/YETHLCQABTQEF Cmqpuss ji/gmzqdg. 7 2 uays Y I] L-IIIIL M NN d1 '8] Y L m 2 L? mm 9 Li 5 QB E 9 4 i 5. ms. 0 WW Q o F m: h 5. NAM o D Z M? n P. vow A 2 o o S. m: 0 mm. o 5. 1 0 j 09 WN o VOIP o C7 o a JP 0 V z o o E (Itl 8, l!@\ Om 0. q: s: HQ w 5H U Q March 3, 1964 K. 1.. CRABTREE ETAL 3,

SPECIAL CARTON PRINTING PRESS Filed Sept. 6. 1961 12 Sheets-Sheet 2 \(7 SI INV EN TORS g W Z ATTOZNEYS March 3, 1 K. L. CRABTREE ETAL 9 SPECIAL CARTON PRINTING PRESS Filed Sept. 5. 1961 12 Sheets-Sheet 3 INVENTORS f Ar 09/105 March 3, 1 K. 1.. CRABTREE ETAL 3,122,994

SPECIAL CARTON PRINTING PRESS l2 Sheets-Sheet 4 Filed Sept. 6. 1961 A emvezwLcqaarpes CHHQLEG 1?. 7710 745, Q-

March 3, 1964 K. L. CRABTREE ETAL 4 SPECIAL CARTON PRINTING PRESS Filed Sept. 6, 1961 12 Sheets-Sheet 5 YZO INVENTORS A EN/YETI-ILCPABrQCT' l l BY A oefleys Cyngws 750-745, d9.

March 3, 1964 K. 1.. CRABTREE ETAL 4 SPECIAL CARTON PRINTING PRESS Filed Sept. 6. 1961 12 Sheets-Sh eet s IN V EN TORS M r 1964 K. CRABTREE ETAL 3,

SPECIAL CARTON PRINTING PRESS 12 Sheets-Sheet 8 Filed Sept. 6. 1961 March 3, 1964 K. L. CRABTREE ETAL 3,122,

SPECIAL CARTON PRINTING PRESS Filed Sept. 6. 1961 12 Sheets-Sheet 9 Tic. 21.

i .151. '23\ b Z30 j W W INVENTORS A aw/ErHLC Asr E: 61141946: f. 75am, JQ.

A ole/76x5 March 1964 K. L. CRABTREE ETAL 3,

SPECIAL CARTON PRINTING PRESS Filed Sept. 6. 1961 12 Sheets-Sheet 10 V INVENTORS ke'flusrallcgqanges r BY C1149 as 59 146, J9.

: HTI'OP/YEYS March 1954 K. L. CRABTREE ETAL 3,122,994

SPECIAL CARTON PRINTING PRESS Filed Sept. 6. 1961 12 Sheets-Sheet ll IN V EN TORS KEN/very! (42487-1956 CAI 29455 71m J March 3, 1964 K. 1.. CRABTREE ETAL 3,122,994

SPECIAL CARTON PRINTING PRESS l2 Sheets-Sheet 12 Filed Sept. 6. 1961 INV EN TORS KEIYIYETHLCQAsr-Qf' Cuneux IQ. Frau-445x19.

United States Patent 3,122,994 SPECIAL CARTGN PRINTING PRESS Kenneth L. Crabtree, Fairfield, Maine, and Charles R.

Thomas, Jr., Cochituate, Mass, assignors to Keyes Fibre Company, Inc., Waterville, Maine, a corporation of Maine Filed Sept. 6, 1961, Ser. No. 136,275 13 Claims. (Cl. 10135) The present invention relates to a special carton print ing press and more particularly relates to a special press for printing on the top and two inclined sides of cartons. The press of this invention may be used for printing on many different kinds of cartons or other products and the description and drawings refer hereinafter to an embodiment arranged for printing on molded pulp paper egg cartons.

In general, the device of this invention may be used on any carton of molded pulp material and is particularly suited to the folding type having a cover section and a pocket section, with the two sections being hingedly joined. Previous devices for printing on this type of carton have many disadvantages which have limited their usefulness. Some of the disadvantages include the lack of adjustments for positioning the impression on the carton with respect to the direction of movement of the carton while the machine is operating and the use of work supports which have failed to position the work accurately so that positive registration between multiple printing heads is insured. This is particularly acute when multi-color printing is being carried out during the passage of the article through a succession of printing stations.

Another serious disadvantage with previous devices has been a marked tendency for them to be slow and unreliable in their operation. The means by which cartons have been carried through printing stations have been unsatisfactory in that carton damage has often occurred at the point of pickup of the carton by the printing press. In view of the inexpensive nature of the type of cartons which are to be printed by the device of this invention it is essential that the device operate automatically and at high rates of speed with a maximum of accuracy and reliability.

Because of the above mentioned disadvantages with prior devices, the device of this invention has as its principal object to provide an automatic carton printing press for either single color or multi-color printing on articles such as molded pulp material cartons at a high rate of speed with a degree of accuracy in registration and reliability in operation not heretofore available.

A further object is to provide a means for carrying articles past a plurality of work stations at a uniform rate by means of platen links so designed and arranged that wear between the link joining means is virtually eliminated.

A further object is to provide a moving work support for a plurality of articles which, as it passes through a work zone, positively positions the work with respect to the working members and insures that the work will be in perfect registration and synchronization with all of the working means.

A still further object is to provide a driving means for a plurality of linked work supports which eliminates backlash and insures that the work will pass through a plurality of working stations at the same linear rate insuring perfect registration between the working member and the work piece at each station. More particularly, it is an object of this invention to provide a plurality of work supports, joined together in end-to-end relationship, which are provided with gear teeth formed along their bottom portion which mesh with a driven gear so that the effect of the plurality of work supports is to form a continuous gear rack.

A further object is to provide a plurality of print heads, each of which is pivotally mounted about its longitudinal drive shaft making possible the adjustment of the depths of impression of the print upon the work Without affecting the drive relationship between the drive shaft and the shaft which is employed to efiect rotation of the print cylinder, and the same pivotal mounting making possible means for spacing the print cylinder away from the printing position when no work piece is present.

A further object is to provide a novel printing press having means for adjusting the position of a plurality of print heads in the direction of the movement of the work without halting the operation of the press.

Another object is to provide a novel printing press for cartons in which eccentric means are used for mounting the drive shaft hearings on which the frames for a plurality of print heads are mounted which permit the positioning of the print heads so as to accommodate cartons of varying Widths.

Another object is to provide novel means for picking up cartons on the work support which insures that no damage will result and that the cartons will be firmly positioned on the work support prior to their entry on the work zone.

In general, the printing press of this invention is designed to print on the top surfaces and two inclined side surfaces of a molded pulp material carton such as a 2 x 6 or 3 x 4 egg carton. Molded cartons, after having been formed by conventional procedure and dried, are delivered by means of a conveyor to the infeed section of the device of this invention. Specially constructed work supports or platens connected in an end-to-end relationship form a continuous belt which picks up the cartons from the infeed conveyor and carry them toward the work zone section.

At the time of pick up, the egg cartons are normally either stationary or moving at a much lower rate of speed than the platens. The infeed conveyor is arranged so that the cartons will be positioned in order that the rapidly moving platens will pick them up as the platen starts its movement toward the printing zone. In previous devices the first point of contact between the carton and the work support was at the lip of the carton or, in other words, at one of the weakest points. This resulted in the tearing of the front wall or other mutilation of the carton. A special feature of this invention is the provision of means for pivoting the front wall of the work support forward so that the initial contact between the moving platen and the stationary carton is over an area on the carton which has sufiicient strength to withstand this sudden acceleration.

The cartons are normally delivered from the drying oven lying downward. Since the only portion which is to be printed is the top section, only the top section need be supported by the platen. Therefore, in the device of this invention, means are provided for camming the pocketed section away from its normally horizontal position so that the inclined side of the top section adjacent the hinge between the top section and the pocketed section can readily be printed upon.

A roll positioned in advance of the printing section insures that the carton top section is properly seated on the work support prior to its entry into the print section. Adjustably mounted bars positioned above the work support further insure that the carton remains firmly seated as it passes into and through the print zone.

In the device of this invention a single or plurality of print zones may be provided. Due to the modular construction of the device of this invention the same intake section and discharge section may be employed with any number of print zones. If single color printing is sufficient, only one print zone is required. For two color or three color printing, a similar number of print zones are employed. Since the top of the carton and the two inclined side portions are to be printed on, a print roll positioned with its axis parallel to the top surface of the carton and the two side print cylinders having their axis of rotation parallel with the inclined surfaces of the sides of the top section are provided for each color to be printed. All of the print cylinders and their associated equipment are carried on brackets which are pivotally connected to longitudinal drive shafts.

Means are provided for positioning, while the machine is in operation, each of the print cyclinders separately in the direction of movement of the carton so that the impression on the carton may be adjusted without stopping the machine. This feature permits the exact registration between colors at various printing stations and permits minute adjustments in registration to be made without halting the machine. Another feature is the provision of means by which the print heads may be rotated about their driving gears in order to prevent printing on a platen when no carton is present thereon. Carton presence indicators are located adjacent each printing head position so as to control the action of a pneumatic cylinder which separately rotates the printing heads away from the work whenever a carton is not in the position to be printed.

The drive shafts for the printing heads are mounted in eccentrics which permit the positioning of the printing heads in either an in position or an out position. The in position is such as to accommodate a fairly narrow width carton whereas the out position is de signed to accommodate a wider carton. The eccentrics permit the same machine to be employed for either width carton without extensive changes in the structure of the machine. By providing several replacement sets of eccentrics any number of varying widths of cartons may be printed on by the same basic machine.

While the platens are moving through the print zone support rollers mounted on the platens are carried by guide rails in such a manner as to positively position the platen during its movement through the printing zone. The support rollers include both horizontally and vertically disposed support roller shafts and roller bearings thus insuring that during the movement of he work through the print zone the work will be in a fixed position with respect to the printing heads both vertically and laterally. The support rollers are likewise used throughout the remaining portions of the system to insure that wear on the paten links is kept at a minimum and that the chain of platen links is positively supported at all time. I

The platen links are so constructed as to have gear teeth on their undersides so that when joined together they form what is in eifect a continuous rack. The in t6lll11k6d platens are driven directly by a spur gear which is positioned beyond the print zone so that during pas" After leaving the print zone the cartons are carried to the discharge section. In this section the carton bottom, which had been previously cammed out of the way, is returned so that, as the carton leaves the discharge station and is stripped from the platens by means of strip}- ping fingers, the carton is once again in a flat position with the open portions of the top and pocketed sections lying face downward. A conveyor of any conventional type is used to carry away the printed carton from the discharge section to stacking machine.

Other objects and novel features will become more apparent after a consideration of the description of the embodiment of this invention illustrated in the figures in which:

FIG. 1 is a side elevation view of the device of this invention.

FIG. 2 is a top plan view of the device shown in FIG. 1.

FIG. 3 is a side elevation view of the intake end unit of the device shown in FIG. 1.

FIG. 4 is a right end view of the intake unit shown in FIG. 3.

FIG. 5 is a plan view of the platen links in partial section of the device illustrated in FIG. 1.

FIG. 6 is a side view of the platen links shown in FIG. 5 and is in partial section illustrating the construction of the platen front wall operating device.

FIG. 7 is a view similar to FIG. 6 showing the movable front wall of the work support in the open position.

FIG. 7A is a cross sectional view of the guide rail structure shown in FIGS. 11 and 21.

FIG. 8 is a partial view of the print zone of the device shown in FIG. 1, illustrating the positioning of the two side print heads with the top print head removed.

FIG. 9 is a top view in partial section of the top, print head. I

FIG. 10 is a cross sectional View of the print zone shown in FIG. 8 taken on the line 1610, showing one side print head.

FIG. 11 is a partial end view of the print zone taken on the line 1l11 of FIG. 2 and in part broken away.

FIG. 12 is a side view in partial section of the top print head illustrated in FIG. 9. 7'

FIG. 13 is a cross sectional view of the top print head section along the line 13-43 of FIG. 12.

FIG. 14 is a view, from the discharge end, of the shifting mechanism for the right side print head, showing no carton safety, depth of impression control, registration control and carton width adjustment.

FIG. 15 is an enlarged top view of detail or the shifting mechanism for the side print head shown in FIG. 14.

FIG. 16 is a cross sectional view of the shifting mechanism along the line 16-16 of FIG. 14.

FIG. 17 is a sectional view taken along line 1717 in FIG. 1, showing the hand wheels for the left and upper print head registration adjustments.

FIG. 18 is a schematic electrical circuit and air supply diagram illustrating the system employed to pivot the print heads out or" contact when no carton is present on the platens.

FIG. 19 is a top view of the drive unit for the device shown in FIG. 1.

FIG. 20 is an elevation view in partial section of the. device shown in FIG. 19.

FIG. 21 is a cross sectional end view of the drive unit taken on the line 21-41 of FIG. 19.

FIG. 22 Ba top view of the drive discharge units of the device illustrated in FIG. 1.

FIG. 23 is a side view in partial section of the drive discharge units illustrated in FIG. 22, and

FIG. 24 is a detailed view in perspective of the carton mounted on the platen as it enters the print unit, showing the hold-down bars.

Referring now to FIGS. 1 and 2, which illustrate an embodiment designed to print a single color on the top inclined surfaces of the top section of a molded pulp paper egg carton, the deviceillustrated in FIG. 1 is arranged so that cartons 25 are fed to the intake unit by an infeed conveyor 32. The intake unit 30 is bolted to base 34 and is removably attached to the print unit 36. Print unit 36 having mounted thereon upper print head 38 and two side print heads 49, 41 is bolted to the base 34. A drive unit 42 is also bolted to base 34 and through drive shafts 44, 46 provides the power for print heads 38, and 41. A discharge end unit 48 bolted to base 34 completes the general arrangement.

In the embodiment illustrated in FIGS. 1 and 2, a single upper printing head 38 and two side printing heads 40, 41 are provided. The print zone may, of course, include a number of upper print heads 38 and pairs of side print heads 49, 41 so that multi-color printing can be carried out on this device. To that end the side printing heads 4t), 41 and upper print heads 3% are separable from each other, and the base 34 may be extended the desired length to include additional side print heads 49, 41 and upper print heads 38.

The following portions of this specification describe the various units in detail.

The Platens Piatens 50 are linked together to form an endless conveyor for cartons 25. The cartons 25 are picked up by the platens 59 ofi an infeed conveyor 32 at the intake unit 30 and are carried through the print 36, drive 42 and discharge 48 units to be carried off by discharge conveyor 52.

As may be seen in FIGS. 5 and 6, each platen 5% includes a carrier link 54 onto which is bolted by bolts 55 a work surface 56. The work surface 56 has a pivotable front end 80 with associated pins and levers all of which are described later in conjunction with the intake unit 3% description. Suffice it to say here that the front end 89 is pivoted out as the Work support 56 picks up a carton 25 in order to meet the carton flush along a side and avoid tearing the carton 25. Adjoining platens 50 are pivotally linked together by a relatively large pin 58, which pin carries two sets of anti-friction roller bearings 60 and 61. In addition each platen has four anti-friction roller bearings 62. Bearings 60, 61 and 62 support, position and guide the platen 50 along guide rail structure 64 in the fashion shown in FIGS. 7A and 21 and described below. Gear teeth 66 are cut into the bottom portion of carrier links 54 and, as shown in FIG. 6, the crown of each tooth is perpendicular to the direction of platen 56 travel and teeth 66 are cut along the whole length of each carrier link 54. Since the carrier links 54 intermesh, the teeth 66 form what is, in elfect, a continuous rack.

A serious problem, indeed one of the major problems, connected with previous presses is the variable distances between work surfaces that results from wear on the roller bearings, wear on the linkages between platens and drive mechanism backlash. Wear of these elements cumulated registration problems which were particularly severe where multiple colors were to be used. In order to make adjustments and replacements, the machine had to be stopped which halted the whole production line and compounded the cost of the attendant delay, making it difficult to keep the carton unit cost down to the very small figure which must necessarily prevail for this type of item.

The roller link chains which have been previously used to carry the work supports are particularly unsatisfactory. The work supports have normally been attached to conventional roller chains which are comprised of a large number of small rollers linked together by links and pins. Such roller chains are normally driven and supported by sprokets at either end of the work zone. As the roller chain passes around the sprokets, wear occurs between the pins and the links. This occurs since there is a slight rotation of the links around the pins as the chain transfers from its flat condition to the curved condition necessary for it to pass around the sprokets. The rotation of the links and the resultant wear on the pins produces a Wearing condition which, though slight with respect to any single pin, is cumulative when all of the pins in the roller chain are considered. After a period of use the cumulative result of the wear on the pins causes a significant shift in the spacing of the work supports in the direction of work support travel.

Added to this difiiculty is the inevitable fact that some pins and links wear at a different rate than other pins and links in the same chain. This means that the magnitude of the shift in work support position along the direction of travel varied as between work supports. With time it becomes impossible to effect any registration (that is, effecting a compensating shift of the print cylinders) that will correct the error for all work supports. A registration adequate for the work support whose linkages have the least wear was inadequate for the work support whose linkages have the greatest wear. correspondingly a registration adequate for the Work support Whose linkages have the greatest wear was too great for the work support whose linkages have the least wear. For a time a compromise registration is possible but as the differential Wear increases it became impossible to effect a proper registration and a replacement of the roller and link chain was necessary with the consequent shutting down of the machine.

This invention has eliminated the wear on the linkages holding the platens and on the pins or rollers that serve to hold the links together and support the links on a track by an entirely new design. Adjacent carrier links 54 are held together by a single large diameter pin 58. Two sets of roller bearings 60 and 61 are on the outer ends of the pin 58 and ride on guide rail structure 64. Thus the pins 58 move along with the platens 50 along the top of the machine and there is no relative motion between the pins 58 and the platens 50 to induce wear. When the platens 56 round either end of the machine, adjoining carrier links 54 must rotate through an arc with respect to each other and as such rotation is about the pin 58 this is the only potential for wear on the pin 58. To eliminate even this wear the pins 58 ride in needle bearings 57. Because of the large diameter of the pins 58, the needle bearings 57 are correspondingly large and so virtually eliminate wear. Oil cups 59 are supplied to keep the needle bearings 57 lubricated. As may be seen in FIG. 5, the needle bearing 57 is only in the central extension 63 of the guide link 54. The pin 58 is press fit into the side extensions 65 of the carrier links 54 so that at no time is there any rotation of the pin 58 with respect to these side extensions 65. All rotation is between the pin 58 and the associated center extension 63 which rides on that pin 58.

Another and closely related source of wear that has been a problem with previous devices has been the wear on the roller bearings that are at times used to support the links on a track. This invention uses roller bearings mounted on the outer ends of each large pin 58. Since the platens 59 are connected as an endless chain they must go around the ends of the machine and return along the base of the machine. A major source of wear on roller bearings used in this fashion is the skipping of the bearings as the platens round either end of the machine to reverse their direction of travel. The bearings skip because they must change their rotational direction, at one end, from counterclockwise to clockwise and vice versa. at the other end. In invention by using two sets of roller bearings 68, 61 guided on separate guide rails 63, 69 disposed as shown in FIG. 17, no roller hearing has to reverse its direction.

Guide rail structure 64 includes guide rails 63 and 69. The inner set of roller bearings 65 are in contact with guide rails 68. Guide rails 68 are two endless continuous tracks along which roller 'bearings 6% are in continous contact during their passage along the top of the machine and during their return trip near the base of the machine. Thus roller bearings 6% support the weight of the platens on the return trip and act as a vertical hold down while the platens pass under the printing rolls and over the spur gear 132. The hold down function of the guide rails 68 is particularly important through the drive unit where the gear :132 engages the gear teeth 66 cut into the bottom of the carrier links 54. When looked at from the left side of the machine (that is the side shown in FIG. 1), the roller bearings 6i will rotate clockwise as the associated platens 5t pass from the intake end to the discharge end of the machine. On the return trip the roller bearings 60 will continue to rotate clockwise since guide rails 68 which bear on bearings 6 from above during the forward trip, bear on bearing 69 from below on the return trip. Thus, the continuous guide rails 63 operate as a hold down on bearings 60 during the forward trip and as a support during the return trip so that the bearings 60 never have to reverse the direction of their rotational motion.

In a very similar fashion, guide rails 69 bear on the outer set of roller bearing 61 in a fashion that maintains the direction of rotational motion of the bearings 61. The roller bearings 61 support the weight of the platens 50 on the forward trip and act as a hold down on the return trip. As seen firom the left side of the machine, roller bearings 61 rotate counter-clockwise during the entire course of their endless track journey on guide rails 69. Thus, in contrast 'with conventional arrangements, the roller hearings do not have to reverse rotational direction and in this fashion does this invention eliminate the skipping of the rollers that is a major cause of roller hearing wear.

Under this guide rail 68, 69 and roller bearing 6G, 61 arrangement the weight of the platens 5t shifts from roller bearings 61 to roller bearings 64 as the platens round the discharge end of the machine to start their return trip. The platens 5G shift their Weight again from bearings 6% to bearings 61 on rounding the intake end. At this area where the weight shifts there is a tendency for the bearings 60, 6 1 to slip and thus wear. A discharge end carmned surface 78 and an intake end cammed surface 71 maintain tension between adjoining platens 56 as they round either end to (reverse their direction of travel. The tension keeps the roller bearings from slipping and eliminates another cause of wear.

By eliminating bot-h skipping, through the special rail 68, 69 arrangement, and slipping, through the cammed ends 70, 71, the bearings 60, 61 will engage the rails 63, 69 with only rolling motion and so will experience virtually no wear.

A rack and gear arrangement is used to eliminate the backlash problem which has beset earlier devices. Gear teeth 66 are out into the underside of the intermeshing carrier links '54 to create what is in effect a continuous and endless rack. A large spur gear 132 in the drive unit 42 (see FIGS. 19 and 2-0) meshes with the rack teeth 66 to assure continuous positive drive and a constant speed of movement for the platens St The guide rail 68 which bears down on roller bearings 69 during passage of the platens through the print 36 and drive 42 units holds the rack teeth 66 down against the gear 132 and cancels the tion of each platen 50 during its passage through the 7 print 36 md drive 42 units.

Bolts 55 are removable so that work surface 56 can be rep-laced by other size work surfaces. The embodiment shown is for a 3 x 4 egg carton but the invention is flexible and can be used for other size cantons, for example a 2 X 6 egg carton.

Intake Unit In order to fully understand the operation of the intake. unit 31) it is necessary to consider the initial steps of manui facture of the pulp paper cartons which are to be printed on by the device of this invention. Conventional pulp forming processes are relied upon to produce the standard.

3 X 4- or 2 X 6 egg cantons. Following their initial formation the cantons are fed to drying ovens and may perhaps be subjected to a final forming action. Delivery of the egg cartons 25 to the intake unit 36 is by means of conveyor 32 which may be of any standard type. In order to make certain that a carton is in proper position to be picked up by a platen 5% it is necessary that the conveyor 32 align the carton 25 properly with respect to the moving platens so and position it so that the initial contact between the moving platen Sil and carton 25 will serve to place it on the platen. A spring finger 76 positioned as, Q

shown in FIGS. 1 and 3 holds down the cartons 25 to counteract a tendency of the moving platens 50 to tip the cartons 25 back, and this assures that the platens 50 will pick up the cartons 25. The spring finger 76 also positions the cartons for proper pick up by the platens 58 and holds them on the platens 5! until the rear end of the carton 25 passes beyond the spring finger '76. By that time the Work support 56 will be in a substantially horizontal position and gravity will retain the canton 25 on the work support 56.

As will be seen in FlGS. 3 and 4, the cartons 25 delivered to the intake unit 3i} lie with their open portions downward on the conveyor 32. As viewed from the conveyor end of intake unit 39, the pocketed section 77 of the cartons 25 is positioned to the left and the cover section 7% is seen as on the right.

One of the serious problems with previous printing devices of this general type has been the tearing of the portion of the carton 25 first coming into contact with work supports which normally move at a much higher speed than the speed at which the cartons are fed to the press. Work support contact of the cover section at its weak lower edge resulted in the tearing or bendin of many cartons. As is set forth above, one of the objects of this invention is to overcome this problem and the means by which this problem has been overcome will now be described.

As best seen in F165. 6 and 7, the front wall 80 of work 7 support 56 is pivotally mounted on pin 82 which is attached to the work support 56. A rod 34 is pivotally attached on one end to front wall 845 by means of a pin 86. The other end of rod 84 is pivotally attached to rocker arm 88 by pin 9% Cam roller 92 is mounted on an end of rocker arm 88. A cam surface 96 bolted to the frame 98 of intake unit St? is positioned so as to engage cam roller 92 as the carrier links 54 are drawn past it. FIG. 5 shows the position of front wall 8% and rocker arm 88 during most of the course of the operation. FIG. 6 shows the positioning of the front wall 80 and rocker arm 88 when the cam roller 92 is at the high point of cam surface96. At this point the front wall 3i? is pivoted to its outer position so that it will contact carton cover '78 flush along the front end portion 97 thus providing a broad area of contact and substantially eliminating the problem of carton 9 tearing at the intake unit 39 of the press. The spring 99 holds the rocker arm 88 in the position shown in FIG. 6 except when cam roller 92 contacts cam surface 96. The spring finger 76 assists in holding the carton 25 against the pivotable front wall 86.

Guide rail structure 64 guides the roller bearings 61'), 61, 62 as the linked together platens 51) start their entry into the print unit 36. A hold down roll 100, which may be powered or not, insures that the carton 25 is properly seated on the work support 56. The convex shape of work support 56 matches the concave cover section 78 of the carton 25 which is to receive the printed matter. The work supports 56 are removably attached by bolts 55 to carrier links 54. The particular shape of the illustrated work support 65 makes it suitable for 3 X 4 egg cartons. In order to accommodate 2 x 6 cartons, or for that matter any difi'erent shape or width cartons, work supports of the proper shape are mounted on carrier link 54. As the carton 25 leaves the intake unit 36 it is properly positioned and ready for printing.

Print Unit On leaving the intake unit 313 the cartons 25, snugly positioned on the work supports 56 by roll 109, are firmly held in place by knife edge stationary bars 104 (see FIG. 24). The bars 184 are adjustably mounted both for vertical and horizontal movement. Bars 194 bear on the top outer corners of the cover section 78 or any other portion thereof which is to remain unprinted.

Stationary cam bar 166 positioned as is shown in FIGS. 1, 2 and 24 is so arranged as to cam the pocketed carton section 26 from the horizontal plane in which it is delivered by the conveyor 32 so that the side of the cover section 78 adjacent the pocketed carton 77 is accessible to the left side printing head 41. As soon as the pocketed carton section 77 is cammed out of the way the carton is then in position for printing.

The top surface 116 of the cover section 78 is first printed on by means of upper print cylinder 112. The upper printing head 38 will be more fully described hereinbelow.

A carton presence indicator lever 114 is positioned slightly in advance of the upper print cylinder 112 and activates a device associated with the mounting bracket 18!) of the upper printing head 38 to pivot head 38 out of the way in the event that no carton is present -on the work support 56 approaching the upper print cylinder 112. A similar carton presence indicator lever 116 is positioned as is shown in FIG. 1 so as to actuate a pivoting device for removing the side print heads 49, 41 from the printing position when no carton is present on the platen 50 adjacent that portion of the print section 36. This pivoting mechanism, which will be more fully described hereinbelow, keeps ink from getting on an empty work support.

The side portions 118 of the cover section 78 are printed on by the side print heads 4:), 41. The peripheral speed of the upper print cylinder 112 and of the side print cylinders 120, 121 is the same as the longitudinal speed of the carton as it passes through the print section 36. Thus, the ink from the print cylinders 112, 120, 121 is applied to the surfaces 116 and 113 in a rolling manner without there being any skidding of the cylinders 112, 121 121 on the cover section 73.

Synchronization between the speed of movement of the platens hence the cartons 25, and the peripheral speed of the print cylinders 112, 12%, 121 is insured by having a common drive unit 42 for the linked together platens 50 and the upper and side printing heads 33, 46, 41.

The cover section 73 of the carton 25 is held firmly in position on the work supports 56 by means of adjustable stationary bars 124 (see FIG. 11) while the cover section 78 is passing through the print unit 36. The pocketed section 77 remains in its out of the way position while the carton 25 is in the print section.

1Q Drive Unit and Discharge Unit Drive unit 42, as may be seen in FIGS. 19, 20, 21, 22 and 23 has adjustable stationary bars 126 attached to a portion of the guide rail structure 64 which in turn is attached to the frame 123. A stationary cam bar 130 cams the pocketed carton section 77 back to a horizontal position by the time the carton 25 leaves the drive unit 42, as may be seen in FIG. 21.

The drive unit 42 contains a large spur gear 132. The gear teeth on the spur gear 132 mesh with gear teeth 66 (see FIG. 20) which are cut into the bottom portion of the carrier links 54. Inasmuch as the carrier links 54 all intermesh, the teeth 66 of one carrier link 54 overlap the teeth 66 of the adjoining carrier link 54 to form what is, in effect, a continuous rack. Since the vertical position of carrier links 54 is determined by the position of roller bearings 61?, 61 in guide rails 68, 69 the drive is uniform. This rack 66 and gear 132 arrangement assures continuous positive drive and thus a constant speed of movement of the platens 50.

As may be seen in FIGS. 20 and 22, spur gear 132 is driven by means of spur gear 136 which is rigidly attached to main drive shaft 138. Main drive shaft 138 is in turn powered by gear reducer unit 140. The drive motor 142 is connected to gear reducer unit 140 by means of belt 144 and variable Reeves drive pulley 145. Drive motor 142 is positioned for horizontal movement which is effected by means of hand wheel 165 to change the speed of operation of the entire device by varying the position of belt 144 in the Reeves pulley 145. This well-known drive system permits the entire device to be run at varying speeds by positioning the drive motor 142. The single speed control provided by the just described systems which in turn operates all of the printing heads 38, 4t), 41 and drives spur gear 132 insures that all parts will be synchronized.

In addition to drive gear 136, printing head shaft drive helical gears 148 are also rigidly attached to main drive shaft 138. Gears 148 mesh with printing head helical gears 150 which are attached to stub shafts 152, 154. Coupling members 156 are used to couple the stub shafts 152, 154, to the respective print head drive shafts 44, 46. The gears 143, 150 are 45 helical gears of substantial width as may be seen in FIGS. 20 and 21. This width makes possible the lateral movement of shafts 152, 154, 44, 46 in eccentric bearing bushings 220 (see FIG. 11) so as to accommodate automatically for cartons of different widths.

Drive shaft 46 operates the right side printing head 40 and upper printing head 38, while drive shaft 44 operates only the left hand printing head 41. The connections between the printing cylinders 112, 120, 121 and the drive shafts 44, 46 will be thoroughly explained below in connection with a discussion of the pivoting and shifting mechanisms of the print heads 38, 40, 41.

A clutch unit 159 permits the operator to disengage the main drive shaft 138 from the gear reducer unit 140 to stop the entire machine and to make it possible for alternate sources of power to be used. In some applications it may be desirable to run this carton press off the same power source as is used for the conveyor belts and other associated machinery either in order to save the cost of a separate power supply or to assure synchronization with other machinery. Under such conditions the clutch permits other power connections to the main drive shaft 138.

As may be seen in FIG. 23, the discharge unit 48 is made up of a frame 158 bolted to the base 34 and to the frame 128 of drive unit 42. For the speed control discussed above, the drive motor 142 (see FIGS. 22 and 23) is mounted on block 162. Block 162 is slideably mounted on a slide 164 and is moved laterally by hand wheel 165. The slide 164 is rigidly attached to shoulder 166 carried on base 34.

As shown in FIG. 23, a cam surface 76, positioned on the outer end of discharge unit 48, is so designed and arranged to insure uniform tension on the interconnected platens 50 as they begin to change from their horizontal direction of movement around the discharge unit 48.

The cartons 25, after passing under stationary bars 126, are no longer held in place on the platens 5i). Carton stripper bars 174 are designed to lift the cartons from the platen 50 and conveyor 52 carries the cartons in their original fiat condition to conventional stacking equipment (not shown).

Print Heads The print heads 38, 40, 41 are adapted to print on the uppermost surface 110 and inclined surfaces 118 of the cover section 78 of cartons 25. Therefore the axis of rotation of upper print cylinder 112 must be parallel with the uppermost surface 110 and the axis of rotation of side print cylinders 126, 121 must be parallel with the inclined surfaces 118. The respective axis of rotation of the cylinders 112, 120, 121 must remain in the same parallel relationship when the heads 38, 4t 41 are shifted in the direction of movement of the cartons for adjustment of the registration of impressions on the surfaces 119, 118, of the cartons 25. This is particularly important when multi-color printing is being done. In addition to the registration of the cylinders 112, 128, 121 in the direction of the carton movement, it is also important to provide for means to adjust the amount of movement of the peripheries of the cylinders 112, 120, 121 toward the cartons 25 so as to control the depth of impression. This adjustment is accomplished in the device of this invention by the shifting mechanism also, as will be fully described below.

Another important feature of the printing heads 38, 40, 41 is the provision of means to remove the cylinders 112, 120, 121 from a printing position when no carton is presout on work supports as they come into the printing position.

Upper print head 38 and right print head are pivotally journalled on the drive shaft 46 (see FIGS. 10, 11), while left print head 41 is pivotally journalled on drive shaft 44. Drive shafts 44, 46, in turn, are supported by eccentric bushings 220 in the frame 178 of print unit 36. In each print head 38, 4t 41 a helical gear 184 is rigidly attached to the cylinder drive shaft 186. Each helical gear 184 is driven by a driving helical gear 182 attached to the appropriate drive shaft 44, 46. Left print head print cylinder 121 and right print head print cylinder 12% are mounted directly on their respective print cylinder drive shafts 186. The location of upper print head print cylinder 112 requires certain additional gearing which is shown in FIG. 13. For the upper print cylinder 112, drive is accomplished by bevel gear 188 keyed to shaft 182 which drives a matching bevel gear 189 attached to drive shaft 190 which in turn rotates the upper print cylinder 112. Gears 192, 194, 196, 198 with their respective shafts 193, 195, 197, 199 all of which derive their power from shaft 1% by means of gear 191 provide the usual ink supply, distribution, and breakdown system to supply ink to the upper print cylinder 112. Ink supply for the cylinder 112 is from a standard ink fountain and pressure ink supply (not shown). Inasmuch as the ink supply, distribution and breakdown are all substantially conventional for all of the print heads 38, 48, 41, no discussion of them is necessary. The drive systems and ink distribution for print heads 48, 41 are similar and need not be further described.

Each print head, including its associated cylinder, is mounted on a separate bracket, 180 designating the upper print head bracket and 181 designating the two side print head brackets. It is through engagement with brackets 180, 181 that the positioning adjustments of the print heads and print cylinders, to be described in detail, is effected. If it is desired to omit printing on one or more sides or on the top, all that need be done is to pivot the particular print head out of the way.

12 Registration Adjustment The three print heads 38, 40, 41 have similar but separate registration adjustments. The adjustment permits movement of the print heads in the direction of travel of the cartons 25 while the machine is in operation. Three hand wheels 2114 are brought out on the left side of the machine by rods 205R, 205L, 205U for ease of access to the operator (see FIGS. 1, 15 and 17). The three hand wheels 2'84 are designated in FIGS. 15 and 17 as 284R, 284L and 2il4U to distinguish the hand wheels 2194 that are used respectively for registration adjustment of the right print head 40, left print head 41, and upper print head 38. As shown in FIG. 15, the hand wheel 2841?. is connected through the machine by a relatively long rod 285 to a gear box 288 and thence, as is described shortl to the registration adjustment mechanism for the right print head 41). Brackets 214, aflixed to print unit frame 1'78, engage rod 285 and support gear box 2 18. FIG. 17 best illustrates the brackets and rods associated with the hand wheels 264 for the left and upper print heads. Since the left print head 41 is operated off a drive shaft 44 which is on the left side of the machine, the rod 282 which connects the hand wheel 2il4L to the gear box 268 is much shorter than the comparable rod 26 5 for the right print head 48 registration adjustment.

A single bracket 215 supports gear box 288 and engages rod 2%2. Part of the left print head 41 adjustment mechanism is shown in MG. 15 to show its general relation to the right print head 40 adjustment mechanism which is described in some detail below.

Referring again to PEG. 17, the hand wheel 2ti4U for upper print head 38 registration adjustment is shown' connected to gear box 288 by a relatively long rod 263. The upper print head 38 being run off right drive shaft 46 must have a rod 263 long enough to pass through the width of the machine. Brackets 216 serve to support the gear box 2% as well as to engage the rod 283.

All other aspects of the registration adjustments for the three print heads 38, 4t 41 are similar so that only one print head adjustment need be illustrated and de scribed in detail. with reference to the right hand print head 40 (see FiGS'. 14, 15 and 16).

The print head 40 is mounted on mounting bracket 181 and rotation of hand wheel 284 causes a collar 206 which bears on bracket 181 to move parallel with the direction of carton 25 travel and thus cause the print head 41 to adjust its registration position. Hand wheel 2114 is connected to gear box 288 by rod 285. Gear box 288 translates the rotational motion of rod 295 into rotational motion of rod 208, rod 289 benig at right angles to rod 2115. Rod 289 is fixed to jack screw block 210. Red 212 has a threaded end which engages the internal threads of jack screw block 210. Two collars 206A and 28613 are pinned onto rod 212, collar 206A 7 screw rotates to draw rod 212 to the left, collar 205A will bear against the right side portion of bracket 181 and move bracket 181, and thus print head 40, to the left, which in the embodiment shown would mean along the direction of travel of cartons 25. Similarly rotation of jack screw 216 to push rod 212 to the right will cause collar 2068 to move bracket 181, and thus print head 40, to the right and against the direction of carton 25 travel.

Bracket 214 engages rod 205 and is aifixed to print unit frame 178. Bracket 219 limits the lengthwise travel of rod 212 when collars 286A and 286B abut bracket 219. Thus a limit is set on the extent of registration adjustment possible. frame 181 so that frame 181 is free to move horizontally towards or away from the machine, to accommodate cartons of varying widths, Without being obstructed by the rod 212 which through its engagement with jack screw The following description is therefore Rod 212 engages an open groove in 13 block 210 is constrained from moving lateral to the machine. A sliding key 218 loosely engages bracket 219 to prevent rotation of rod 212 during the lengthwise travel of rod 212.

Since the driving gears 182, 184 for the print head are helical the longitudinal movement does not affect the driving relationship up to the limit of the width of the gears. The sliding key 218 assures that the rod 212 will not rotate and bracket 219 assures that collar 206 will not carry rod 212 far enough to disengage gears 182, 184. The lateral movement of the driven helical gear 134 with respect to the driving helical gear 182 will cause rotation of the driven helical gear 184 and thus rotation of the print cylinder 121. However rotation of the print cylinder 121 effects a registration adjustment as much as does lateral movement of the cylinder. The direction of registration adjustment from cylinder 121 rotation will oppose the direction of registration adjustment from lateral cylinder movement. Thus it is important to avoid a relationship between type cylinder 121 and gear 182, 184 diameters which will cause them to cancel out each others registration effect. For example, an operative embodiment may have a 9.620 inch diameter cylinder and helical gears with a 5.000 inch pitch diameter. A one inch lateral movement of the type cylinder 121 requires the driven gear 184 to rotate one inch of circumference, which on a 5.000 pitch diameter is 22.9 degrees. Thus the type cylinder 121 must also rotate 22.9 degrees, which on a 9.620 inch diameter is circumferential distance of 1.920 inches. Thus the net registration on the type face effected for one inch of lateral movement is 0.920 inch.

Carton Width Adjustment The print head drive shafts 44, 46 and their associated stub drive shafts 152, 154 are mounted in the print unit frame 178 and the drive unit frame 160 on eccentric bearing bushings 220. Rotation or replacement of these bushings makes possible a quick and simple adaptation to cartons of varying widths. In the out position of the eccentric bushing 220, as shown in FIGS. 11 and 14, the device of this invention is set to print on 3 x 4 egg cartons. A 180 rotation of each bushing 220 will reposition drive shafts 44, 46, 152, 154 causing print head brackets 180, 181, which are carried by drive shafts 44, 46 to move closer to the platen 50 track and thus accommodate for a 2 x 6 egg carton. If yet other carton width positions are desired, eccentric bushing 220 may be replaced with another eccentric bushing having different eccentricity. The carton width adjustment does not change the angle of inclination of the printing heads and thus provides a very simple change-over from a 3 x 4 to a 2 x 6 egg carton printing run.

Bracket 219 carries a number of the elements associated with other adjustments, registration, depth of impression and no-carton safety. When the entire print head 40 is adjusted for a new carton width, the bracket 219 must be concurrently shifted to avoid interfering with the arrangements for the other adjustments. Exactly why this is so will be clear after understanding the no-carton safety and depth of impression adjustments which are described next. Suffice it to point out here that the bracket 219 is fixed to the print head frame 178 by removable bolts 221 through slotted holes 226. When the eccentric bushing 220 is rotated, bolts 221 must be loosened and the bracket 219 shifted until the arrangement of the T handle 235 and air cylinder 232 is restored to that shown in FIGS. 14, 15 and 16. The bolts 221 are then tightened and the bracket 219 becomes afiixed to frame 178.

When the side print heads 40, 41 have moved laterally in response to the bushing 220 adjustment, their respective print cylinders 120, 121 will have moved in with respect to the central axis of the machine, assuming a change-over from a 3 x 4 to a 2 x 6 egg carton. The print cylinders 120, 121 will then be in an appropriate position to print on the carton 25 sides which are closer to the central axis of the machine. However this lateral shift of the print heads 40, 41 through a lateral shift of the drive shafts 44, 46 also causes lateral movement of the upper print cylinder 112 since the upper print head 38 is mounted on the drive shaft 46. This lateral movement is lateral with respect to the direction of travel of the platen 50 chain. The upper print cylinder 112 is broad enough so that even after such lateral movement the cylinder 112 will still cover the top surface to be printed. All that is necessary is that the type face put on the print cylinder be placed on that part of the cylinder 112 which will engage the carton 25 surface to be printed.

The work surface 56 on each platen 50 must concurrently be changed when the carton width adjustment is made and as explained earlier this is readily done by removing the bolts 55 which hold the work surface 56 onto the carrier link 54.

The only other change necessary is to adjust the stationary bars 104, 124, 126 so that their distance apart corresponds to the width of the 2 x 6 egg carton. Since stationary bars 104, 124, 126 are all mounted on brackets 228 by bolts that engage the brackets 223 through elongated slots (see FIG. 8) the distance apart can be readily adjusted.

N0 Carton Safety When a work surface 56 comes through the print unit 36 without a carton, the print heads 38, 40, 41 pivot out to avoid inking the work surface 56 and thus avoid messing the inside of successive cartons 25 carried by that work surface. Two carton presence indicator levers 114, 116 are positioned as shown in FIG, 1. When no carton is present, the levers 114, 116 will pivot sufficiently to actuate switches 230, 231 respectively, schematically shown in FIG. 18. When so actuated switches 230, 231

connect a source of compressed air to each of three air cylinders 232, forcing the air cylinders 232 upward and causing each print head 38, 40, 41 to pivot away from the work surface. When a carton is present on a work surface, the levers 114, 116 are raised, the air cylinders 232 are de-energized and the springs 234 (see FIGS. 14, 15 and 16), will pull the print heads back to a print position. The levers 114, 116 have a trailing end long enough so that they will remain raised throughout the passage of a carton 25 through the print zone. Thus the levers 114, 116 will not pivot down in response to an empty work support 56 until the prior work support has cleared the associated print zone.

A separate air cylinder 232 exists for each print head. The Whole pivoting arrangement, except for the levers 114, 116 and the switches 230, 231 is separate for each print head. But since the pivoting arrangement is similar for each print head, only the arrangement for the right print head 40 need be described. This arrangement is shown in FIGS. 14, 15 and 16.

T handle 235 is pivotally mounted on the frame 178 of print section 36 by means of pin 236. Pin 237 is mounted on its ends in bracket 181 and on its center portion engages T handle 235. An extension portion 238 of T handle 235 extends over air cylinder 232 and when air cylinder 232 is in its normally de-energized condition there is clearance between it and extension portion 238. When an empty work surface 56 comes along, the air cylinder 232 pushes up against extension portion 238, causing T handle 235 to pivot about pin 236 and by engagement of pin 257 force bracket 181 to pivot out. Print head 40 is mounted on bracket 181 and is pivotally connected to drive shaft 44, through gears 182, 184 so that it can pivot under pressure from T handle 235 and pin 237. Two springs 234 are connected to T handle 235 and will rotate the print head 41) back into print position when the air cylinder 232 again becomes de-energized.

Depth of Impression Adjustment Eccentric cams 240 mounted, as shown in FIGS. 14

15 and 16, on pins 242 permit control of the depth of impression made by the side print heads 40, 41 on the cart'on surfaces. Both side print heads 45, 41 have separate but similar depth of impression controls so that only the control for the right print head 4t) will be described or illustrated.

The cam 240 abuts against the arm portion 244 of movable T handle 235 affording an additional control on the T handle 235 over the no-carton safety control above described. Rotating hand wheel 246 on pin 242 rotates cam 249 causing slight pivotal movement of T handle 235 about pin 236. T handle 235 then rotates the print head 40 through engagement with pin 237 as described under the no-carton safety control. Cam 240 also serves as the stop for T handle 235 limiting its rotation under the influence of springs 234. The clearance between air cylinder 232 and extension portion 238 is required so that the T handle 235 can rotate as the cam 240 rotates. It is of considerable value that the depth of impression adjustment can be made while the machine is in operation so that a production line need not be stopped.

The pivotal arrangement of the print heads 46, 41 permits this adjustment to be made without affecting the drive relationship between gears 182, 184 and thus eliminates the backlash problem associated with this type of adjustment in other machines.

A parallelism adjustment for the upper print head 38 operates in a similar manner to the depth of impression adjustment just described for the side print heads. Rotation of the cam 24%) and pivoting of the T mechanism 235 associated with the upper print head 38 pivots that print head about the drive shaft 46 in a manner identical with the pivoting of the side print heads 40, 41 about their drive shafts 44, 45. The upper print cylinder 112 which is part of print head 38 in rotating about drive shaft 46 tilts away from the plane of the carton 25 top at too sharp an angle for such adjustment to be useful as a depth of impression control. Therefore rotation of the handle 246 associated with the upper print head 38 serves as an adjustment of the parallelism between the print cylinder 112 surface and the carton 25 top surface.

The depth of impression control for the upper print head 38 is best illustrated in FIGS. 9 and 12. Two hand wheels 222 are connected to rods 223, having jack screws 224- on their center portions. Jack screw blocks 225, which engage jack screws 224, are fixed to a secondary frame 227 which frame is slidably mounted in bracket 18%. As handles 222 are turned, rotating jack screws 224, the block 225 and secondary frame 227 are raised or lowered inside of the bracket 18%. The print cylinder 112 and most of the elements of the print head 38 are mounted on the secondary frame 227 so that the vertical adjustment of the secondary frame 227 is a depth of impression adjustment for the upper print cylinder 112.

The device of the invention is versatile in that many different shapes and sizes of cartons can be printed on with it. The device is also highly reliable in that wear is reduced far beyond that of other known presses. Registration and depth of impression adjustments can be made while the machine is in operation and this feature, together with its high reliability, greatly reduces the amount of down time for the machine, thus decreasing the total cost of operation and reducing the associated cost of holding up a production line.

Although the invention has been described with a certain degree of particularity and many variations in operation illustrated, it is to be understood that the present disclosure is by way of example and that changes in the details of construction and operation will be apparent to one skilled in the art and can be made without departing from the scope and claims of the invention.

For example, the unitized design permits any number of print units to be inserted between the intake and drive units so that multi-color printing may be had. Similarly, the adjustments necessary to accommodate to print on a wide variety of cartons or objects are essentially minor and would not require invention.

Certain variations in the guide rail structure may be desired and could be made Within the scope of this invention. The embodiment described carries both guide rails all around the machine to assure that both sets of roller bearings remain in rotation. Under some conditions it may be unnecessary to avoid possible wear as one set accelerates from zero to normal rotational speed. Thus the outer guide rails 69 need not be carried all around the machine and the outer roller bearings 61 Will not be in rotation on the return trip through the base.

It is intended therefore in the appended claims to cover all such modifications as fall within the true scope of the invention.

I claim:

1. A carton printing press having printing means for printing on a continuously moving carton, and endless platen means for transporting cartons through a printing zone where said printing means is located, said platen means comprisin. a plurality of separate work supports carried on one side of platen links, a connecting pin pivotally linking together successive ones of said platen links, gear teeth formed on the side of said platen links opposite said work supports, said gear teeth on said platen links forming what is in effect a continuous and endless rack, driving means in mesh with said rack for continuously moving said platen links in one direction through said printing zone and for continuously returning said platen links in a reverse direction for subsequent movement in said first direction through said printing zone, two sets of roller hearings on each of said connecting pins to vertically position said platen links during their movement in each of said directions, each set of said roller bearings running on a separate guide rail, one of said guide rails being so disposed that one set of said roller bearings always rotates clockwise and the other of said guide rails eing so disposed that the other set of said roller bearings always rotates counterclockwise during said continuous movement in each of said directions.

2. A carton printing press having printing means for printing on a continuousl moving carton; endless platen means for transporting cartons through a printing zone where said printing means is located; said platen means comprising a plurality of separate work supports carried on one side of platen links, a connecting pin pivotally linking together successive ones of said platen links, gear teeth formed on the side of said platen links opposite said work supports, said gear teeth on said platen links forming what is in effect a continuous and endless rack, driving means in mesh with said rack for continuously moving said platen links in one direction through said printing zone and for continuously returning said platen links in a reverse direction for subsequent movement in said first direction through said printing zone, two sets of roller hearings on each of said connecting pins to vertically position said platen links during their movement in each of said directions, each set of said roller bearings running on a separate guide rail, one of said guide rails being so disposed that one set of said roller bearings always rotates clockwise and the other of said guide rails being so disposed that the other set of said roller bearings always rotates counterclockwise during said continuous movement in each of said directions; and cammed surfaces at both ends of said press 

1. A CARTON PRINTING PRESS HAVING PRINTING MEANS FOR PRINTING ON A CONTINUOUSLY MOVING CARTON, AND ENDLESS PLATEN MEANS FOR TRANSPORTING CARTONS THROUGH A PRINTING ZONE WHERE SAID PRINTING MEANS IS LOCATED, SAID PLATEN MEANS COMPRISING A PLURALITY OF SEPARATE WORK SUPPORTS CARRIED ON ONE SIDE OF PLATEN LINKS, A CONNECTING PIN PIVOTALLY LINKING TOGETHER SUCCESSIVE ONES OF SAID PLATEN LINKS, GEAR TEETH FORMED ON THE SIDE OF SAID PLATEN LINKS OPPOSITE SAID WORK SUPPORTS, SAID GEAR TEETH ON SAID PLATEN LINKS FORMING WHAT IS IN EFFECT A CONTINUOUS AND ENDLESS RACK, DRIVING MEANS IN MESH WITH SAID RACK FOR CONTINUOUSLY MOVING SAID PLATEN LINKS IN ONE DIRECTION THROUGH SAID PRINTING ZONE AND FOR CONTINUOUSLY RETURNING SAID PLATEN LINKS IN A REVERSE DIRECTION FOR SUBSEQUENT MOVEMENT IN SAID FIRST DIRECTION THROUGH SAID PRINTING ZONE, TWO SETS OF ROLLER BEARINGS ON EACH OF SAID CONNECTING PINS TO VERTICALLY POSITION SAID PLATEN LINKS DURING THEIR MOVEMENT IN EACH OF SAID DIRECTIONS, EACH SET OF SAID ROLLER BEARINGS RUNNING ON A SEPARATE GUIDE RAIL, ONE OF SAID GUIDE RAILS BEING SO DISPOSED THAT ONE SET OF SAID ROLLER BEARINGS ALWAYS ROTATES CLOCKWISE AND THE OTHER OF SAID GUIDE RAILS BEING SO DISPOSED THAT THE OTHER SET OF SAID ROLLER BEARINGS ALWAYS ROTATES COUNTERCLOCKWISE DURING SAID CONTINUOUS MOVEMENT IN EACH OF SAID DIRECTIONS. 